New immune system discovered

May 20, 2013
by Natalia Van Stralen

(Medical Xpress)—A research team, led by Jeremy Barr, a biology post-doctoral fellow, unveils a new immune system that protects humans and animals from infection.

Mucus may be slimy and gross, but a San Diego State University research team, led by Biology Post-doctoral Fellow Jeremy Barr, has discovered that it is also home to a powerful immune system that could change the way doctors treat a number of diseases.

In this previously undocumented immune system, researchers uncovered bacteria-infecting viruses known as bacteriophage, which shield the body from invading infection.

The discovery, made possible with funding from the National Institutes of Health, concentrates on the protective layers of mucus which are present in all humans and animals. It serves both as a home for large populations of beneficial microbes—which can include fungi, bacteria and viruses—and as an entry point for infection.

A new immune system

The researchers sampled mucus from animals and humans—ranging from a sea anemone to a mouse and a person—and found that bacteriophage adheres to the mucus layer on all of them.

They placed bacteriophage on top of a layer of mucus-producing tissue and observed that the bacteriophage formed bonds with sugars within the mucus, causing them to adhere to the surface. They then challenged these mucus cells with E. coli bacteria and found that the bacteriophage attacked and killed off the E. coli in the mucus, effectively forming an anti-microbial barrier on the host that protected it from infection and disease.

To confirm their discovery, the team also conducted parallel research challenging non-mucus producing cells with both bacteriophage and E. coli. The results—the samples with no mucus had three times more cell death.

"Taking previous research into consideration, we are able to propose the Bacteriophage Adherence to Mucus—or BAM—is a new model of immunity, which emphasizes the important role bacteriophage play in protecting the body from invading pathogens," Barr said.

A hidden protector

According to Barr, part of what makes this research so novel is that bacteriophage are already present on all humans and animals.

The body recruits the bacteriophage from the environment, which then naturally sticks to mucus layers across various parts of the body including the mouth and gut. The bacteriophage then becomes a protector of its host, accumulating and attacking on its own.

"This discovery not only proposes a new immune system but also demonstrates the first symbiotic relationship between phage and animals," Barr said. "It will have a significant impact across numerous fields."

"The research could be applied to any mucosal surface," Barr said. "We envision BAM influencing the prevention and treatment of mucosal infections seen in the gut and lungs, having applications for phage therapy and even directly interacting with the human immune system."

The research was published in the May Early Edition of the journal Proceedings of the National Academy of Sciences.

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9 comments

It surprises me how much we still have to learn - even about our own bodies. In some ways it is encouraging - what will things look like when we really start to put all the pieces together - in others ways it is discouraging - so much still to learn - and so many head winds.

This article - To be 'Human' is to be so much more than we really realize. We are such a congregation of complex parts that are synchronized to function as a sentient entity probing its own universe while being host to so many other living things such that over 92% of every person is NOT THAT PERSON and has independent life and dependence on us FOR life! It is like one day a vast array of living organisms got together and said, " Hey lets get together and become man!" And, they all knew what they were talking about...Dayyum!

HUmmm, I wonder if there is cosmic relevance here....our world, to the known universe; US to our microscopic allies? Does it scale proportionately? What do you think?

I think there is tendency to romanticize the world - and not to understand the full spectrum. Here are some pictures of the effects of septicaemia - https://www.googl...pictures of septicaemia&tbm=isch&tbo=u&source=univ&sa=X&ei=3Q-bUcPKJ4WQ8wToxIGoDA&ved=0CDEQsAQ&biw=1600&bih=775 Caused by our 'microscopic allies'. I don't see the universe the same way you do. I think the process of our evolution is to understand this chaotic process - not to see it as some cosmic perfection.

210 "US to our microscopic allies?"I think there is tendency to romanticize the world - and not to understand the full spectrum. Here are some pictures of the effects of septicaemia - perfection.

Yes, oh negative one, our microscopic allies. They digest our food, and fight our infections and according to the article, they fight for our lives in ways we have only just discovered. They HELP keep us on this planet by eating the oil BP likes to spill in megatons. The question I asked was aimed at the large, the macro and micro scales. You thought you would sound hip and cool and take it all out of context....nobody questioned evolution, you bought it up, no body romanticized a damn thing that was you....again! Then you ran out and got a picture to show us of your family tree...more than 92% of all our cells are not ours, and for you, that is probably the closest intimate relationship YOU will ever have, EVER! (Dinner and a movie is just U & the bugs!)word-

To be honest, please note that the size of bacteria is way smaller than human cells. What's that 92% by volume? I'm guessing a very small number.

These are species that have found niches and figured out ways to live in association with us without killing us (at least before we have had a chance to reproduce). I guess my view of the world is less rosy than yours; we do, after all, have the need for the sophisticated immune systems we have.

Final thought: consider how poorly behaved our bacterial "partners" become the immune system is shut down.

210 - "You thought you would sound hip and cool and take it all out of context..."

I don't think I took anything out of context - you were the one referred to bacteria as 'our microscopic allies' and then started throwing around terms like 'cosmic relevance'. I stand by my position - that there is a tendency to be romantic about stuff - and not to be realistic about the chaotic nature of it all - bacteria sit in our gut and digest our food for us, and they bring us hideous diseases. I am just saying recognize the good with the bad.

The symbiotic ordering between animal hosts and bacteriophage is recapitulated at large in the inter-relationships of biosphere, lithosphere and noosphere. See Vladimir Vernadsky's work for comparison.

The bacteriophage as an "immune system" is not new knowledge, there are already commercial products that use them singularly and in multiples(attack mechanisms)to combat bacterial infections and even more products in development.